Organofunctional silicone compounds are one of two types, internal and terminal depending upon the location of the silicone group.
The so-called terminal group has the organic functional groups at the alpha and omega terminus of the molecule. Typical; of this class of compounds is the class of compounds currently called bis-dimethicone conforming to the following structure:
In the case where R is —(CH2)3—O—(CH2CH2O)8H the compound is bis PEG-8 dimethicone.
The other type of compound is referred to as comb structure in which the organofunctionality is located on non-terminal ends of the molecule. This type of compound is called a “comb” compound since the organofunctionality lies in the molecule much like the teeth of a comb. These compounds are shown in the following structure:
In the case where R is —(CH2)3—O—(CH2CH2O)8H the compound is simply PEG-8 dimethicone.
The present invention is directed to compounds in of the comb type having two different “R” groups. Such compounds have been disclosed in the so-called comb alkyl dimethicone copolyol class.
In the case where R1 is —(CH2)3—O—(CH2CH2O)8H and R2 is —(CH2)11—CH3 the compound is lauryl PEG-8 dimethicone. Such compounds are known and U.S. Pat. No. 7,279,503 to O'Lenick, incorporated herein by reference, is typical of patents related to such compounds. These compounds have two different types of compounds present on the molecule, in this case alkyl and alkoxylated.
We have surprisingly found that when two different level of alkoxylation are placed on one molecule the surfactant properties of the resulting emulsifier can be improved. None of the prior art known to us disclose such a compound.